Overview
ISO 23792-2:2026 outlines the requirements and test procedures for discretionary lane change (DLC) functionalities in motorway chauffeur systems (MCS) performing Level 3 automated driving. This international standard, developed by the International Organization for Standardization (ISO), focuses on light vehicles equipped with MCS for use on limited access motorways. DLC allows a vehicle to change lanes independently under specific conditions, enhancing the system’s overall automated driving capabilities. This standard complements ISO/TS 23792-1 by specifying additional requirements and test methods for safe and reliable discretionary lane changes, excluding route selection and destination setting features.
Key Topics
- Discretionary Lane Change (DLC):
Defines criteria for when and how a motorway chauffeur system can perform lane changes not strictly required for route continuation, including overtaking or user-initiated changes.
- System State Management:
Details operational states (off, standby, active) for DLC functions, including transitions and conditions triggering engagement or disengagement.
- Detection Functions:
Specifies requirements for detecting lane markings, traffic signs, and sufficient gaps in surrounding traffic to support safe lane changes.
- Driver Interface:
Addresses the interface between the system and the fallback-ready user (FRU), including notifications, controls, and take-over requests.
- Performance Requirements:
Prescribes minimum performance criteria such as maneuver duration and operational limits for automated lane changes.
- Test Procedures:
Outlines conditions and methods for verifying DLC functionality, including environmental scenarios, lane availability, sufficient gap assessment, and system response to manual override or cancellation.
Applications
Adopting ISO 23792-2:2026 brings practical benefits in the deployment and assessment of intelligent transport systems and Level 3 automated driving technologies:
- Automotive Manufacturers:
Ensure that advanced driver assistance systems (ADAS) and MCS implementations for light vehicles comply with internationally recognized safety and reliability criteria for lane change automation.
- Testing and Certification Bodies:
Use standardized test procedures for DLC, facilitating conformity assessment and regulatory approval for automated driving features.
- System Developers and Integrators:
Rely on explicit functional and interface requirements to guide the development and integration of robust, user-friendly DLC capabilities within larger automated driving platforms.
- Fleet Operators and Mobility Services:
Specify and select vehicles with MCS conforming to ISO standards, supporting consistent operational performance and safety across diverse motorway environments.
Related Standards
For a comprehensive approach to automated driving systems (ADS) and motorway automation, consider the following related standards:
- ISO/TS 23792-1: Intelligent transport systems - Motorway chauffeur systems (MCS) - Part 1: Framework and general requirements
Fundamental requirements for MCS design and operation.
- ISO 17387:2008: Lane change assistance systems for road vehicles - Performance requirements and test procedures
Reference for gap detection ranges and supporting functions.
- ISO 26262: Road vehicles - Functional safety
Framework for automotive safety integrity levels, highly relevant in automated vehicle development.
- SAE J3016: Taxonomy and definitions for terms related to driving automation systems
Provides definitions for different driving automation levels, including Level 3 systems covered by this standard.
By following ISO 23792-2:2026, stakeholders in the intelligent transport systems domain can achieve higher levels of safety, system interoperability, and public confidence in motorway chauffeur systems capable of discretionary lane changes. This standard plays a crucial role in enabling the responsible and scalable rollout of Level 3 automation in real-world motorway contexts.
Open preview (PDF)Intelligent transport systems — Motorway chauffeur systems (MCS) — Part 2: Requirements and test procedures for discretionary lane change
